Dreaming of being stabbed

I just woke up from a bit of a nightmare! From what I remember of my dream is I saw this guy get into a car and had a knife with him and I was going to report it to the police. But the car came back round as I had my mobile out and this guy got out,

It felt so real, so scary the guy had a knife against me, after what seemed a lifetime I work up scared to return to sleep.

I don’t know where this dream came from, was it the news? Reporting every knife crime that has happened in London or something deeper? Hopefully this horrible feeling in my gut will pass…